src/msw/button.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        msw/button.cpp
   3 // Purpose:     wxButton
   4 // Author:      Julian Smart
   5 // Modified by:
   6 // Created:     04/01/98
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) Julian Smart and Markus Holzem
   9 // Licence:     wxWindows license
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 // ============================================================================
  13 // declarations
  14 // ============================================================================
  15
  16 // ----------------------------------------------------------------------------
  17 // headers
  18 // ----------------------------------------------------------------------------
  19
  20 #ifdef __GNUG__
  21     #pragma implementation "button.h"
  22 #endif
  23
  24 // For compilers that support precompilation, includes "wx.h".
  25 #include "wx/wxprec.h"
  26
  27 #ifdef __BORLANDC__
  28     #pragma hdrstop
  29 #endif
  30
  31 #if wxUSE_BUTTON
  32
  33 #ifndef WX_PRECOMP
  34     #include "wx/button.h"
  35     #include "wx/brush.h"
  36     #include "wx/panel.h"
  37     #include "wx/bmpbuttn.h"
  38     #include "wx/settings.h"
  39     #include "wx/dcscreen.h"
  40 #endif
  41
  42 #include "wx/msw/private.h"
  43
  44 // ----------------------------------------------------------------------------
  45 // macros
  46 // ----------------------------------------------------------------------------
  47
  48 IMPLEMENT_DYNAMIC_CLASS(wxButton, wxControl)
  49
  50 // this macro tries to adjust the default button height to a reasonable value
  51 // using the char height as the base
  52 #define BUTTON_HEIGHT_FROM_CHAR_HEIGHT(cy) (11*EDIT_HEIGHT_FROM_CHAR_HEIGHT(cy)/10)
  53
  54 // ============================================================================
  55 // implementation
  56 // ============================================================================
  57
  58 // ----------------------------------------------------------------------------
  59 // creation/destruction
  60 // ----------------------------------------------------------------------------
  61
  62 bool wxButton::Create(wxWindow *parent,
  63                       wxWindowID id,
  64                       const wxString& label,
  65                       const wxPoint& pos,
  66                       const wxSize& size,
  67                       long style,
  68                       const wxValidator& validator,
  69                       const wxString& name)
  70 {
  71     if ( !CreateControl(parent, id, pos, size, style, validator, name) )
  72         return FALSE;
  73
  74     WXDWORD exstyle;
  75     WXDWORD msStyle = MSWGetStyle(style, &exstyle);
  76
  77 #ifdef __WIN32__
  78     // if the label contains several lines we must explicitly tell the button
  79     // about it or it wouldn't draw it correctly ("\n"s would just appear as
  80     // black boxes)
  81     //
  82     // NB: we do it here and not in MSWGetStyle() because we need the label
  83     //     value and m_label is not set yet when MSWGetStyle() is called;
  84     //     besides changing BS_MULTILINE during run-time is pointless anyhow
  85     if ( label.find(_T('\n')) != wxString::npos )
  86     {
  87         msStyle |= BS_MULTILINE;
  88     }
  89 #endif // __WIN32__
  90
  91     return MSWCreateControl(_T("BUTTON"), msStyle, pos, size, label, exstyle);
  92 }
  93
  94 wxButton::~wxButton()
  95 {
  96 }
  97
  98 // ----------------------------------------------------------------------------
  99 // flags
 100 // ----------------------------------------------------------------------------
 101
 102 WXDWORD wxButton::MSWGetStyle(long style, WXDWORD *exstyle) const
 103 {
 104     // buttons never have an external border, they draw their own one
 105     WXDWORD msStyle = wxControl::MSWGetStyle
 106                       (
 107                         (style & ~wxBORDER_MASK) | wxBORDER_NONE, exstyle
 108                       );
 109
 110     // we must use WS_CLIPSIBLINGS with the buttons or they would draw over
 111     // each other in any resizeable dialog which has more than one button in
 112     // the bottom
 113     msStyle |= WS_CLIPSIBLINGS;
 114
 115 #ifdef __WIN32__
 116     // don't use "else if" here: weird as it is, but you may combine wxBU_LEFT
 117     // and wxBU_RIGHT to get BS_CENTER!
 118     if ( style & wxBU_LEFT )
 119         msStyle |= BS_LEFT;
 120     if ( style & wxBU_RIGHT )
 121         msStyle |= BS_RIGHT;
 122     if ( style & wxBU_TOP )
 123         msStyle |= BS_TOP;
 124     if ( style & wxBU_BOTTOM )
 125         msStyle |= BS_BOTTOM;
 126 #endif // __WIN32__
 127
 128     return msStyle;
 129 }
 130
 131 // ----------------------------------------------------------------------------
 132 // size management including autosizing
 133 // ----------------------------------------------------------------------------
 134
 135 wxSize wxButton::DoGetBestSize() const
 136 {
 137     wxString label = wxGetWindowText(GetHWND());
 138     int wBtn;
 139     GetTextExtent(label, &wBtn, NULL);
 140
 141     int wChar, hChar;
 142     wxGetCharSize(GetHWND(), &wChar, &hChar, &GetFont());
 143
 144     // add a margin - the button is wider than just its label
 145     wBtn += 3*wChar;
 146
 147     // the button height is proportional to the height of the font used
 148     int hBtn = BUTTON_HEIGHT_FROM_CHAR_HEIGHT(hChar);
 149
 150     if (!HasFlag(wxBU_EXACTFIT))
 151     {
 152         wxSize sz = GetDefaultSize();
 153         if (wBtn > sz.x) sz.x = wBtn;
 154         if (hBtn > sz.y) sz.y = hBtn;
 155         return sz;
 156     }
 157     else
 158         return wxSize(wBtn, hBtn);
 159
 160 }
 161
 162 /* static */
 163 wxSize wxButtonBase::GetDefaultSize()
 164 {
 165     static wxSize s_sizeBtn;
 166
 167     if ( s_sizeBtn.x == 0 )
 168     {
 169         wxScreenDC dc;
 170         dc.SetFont(wxSystemSettings::GetFont(wxSYS_DEFAULT_GUI_FONT));
 171
 172         // the size of a standard button in the dialog units is 50x14,
 173         // translate this to pixels
 174         // NB1: the multipliers come from the Windows convention
 175         // NB2: the extra +1/+2 were needed to get the size be the same as the
 176         //      size of the buttons in the standard dialog - I don't know how
 177         //      this happens, but on my system this size is 75x23 in pixels and
 178         //      23*8 isn't even divisible by 14... Would be nice to understand
 179         //      why these constants are needed though!
 180         s_sizeBtn.x = (50 * (dc.GetCharWidth() + 1))/4;
 181         s_sizeBtn.y = ((14 * dc.GetCharHeight()) + 2)/8;
 182     }
 183
 184     return s_sizeBtn;
 185 }
 186
 187 // ----------------------------------------------------------------------------
 188 // default button handling
 189 // ----------------------------------------------------------------------------
 190
 191 /*
 192    "Everything you ever wanted to know about the default buttons" or "Why do we
 193    have to do all this?"
 194
 195    In MSW the default button should be activated when the user presses Enter
 196    and the current control doesn't process Enter itself somehow. This is
 197    handled by ::DefWindowProc() (or maybe ::DefDialogProc()) using DM_SETDEFID
 198    Another aspect of "defaultness" is that the default button has different
 199    appearance: this is due to BS_DEFPUSHBUTTON style which is completely
 200    separate from DM_SETDEFID stuff (!).
 201
 202    Final complication is that when a button is active, it should be the default
 203    one, i.e. pressing Enter on a button always activates it and not another
 204    one.
 205
 206    We handle this by maintaining a permanent and a temporary default items in
 207    wxControlContainer (both may be NULL). When a button becomes the current
 208    control (i.e. gets focus) it sets itself as the temporary default which
 209    ensures that it has the right appearance and that Enter will be redirected
 210    to it. When the button loses focus, it unsets the temporary default and so
 211    the default item will be the permanent default -- that is the default button
 212    if any had been set or none otherwise, which is just what we want.
 213
 214    Remark that we probably don't need to send DM_SETDEFID as we don't use
 215    ::IsDialogMessage() (which relies on it) any longer but OTOH it probably
 216    doesn't hurt neither.
 217  */
 218
 219 // set this button as the (permanently) default one in its panel
 220 void wxButton::SetDefault()
 221 {
 222     wxWindow *parent = GetParent();
 223
 224     wxCHECK_RET( parent, _T("button without parent?") );
 225
 226     // set this one as the default button both for wxWindows and Windows
 227     wxWindow *winOldDefault = parent->SetDefaultItem(this);
 228     ::SendMessage(GetWinHwnd(parent), DM_SETDEFID, m_windowId, 0L);
 229
 230     UpdateDefaultStyle(this, winOldDefault);
 231 }
 232
 233 void wxButton::SetTmpDefault()
 234 {
 235     wxWindow *parent = GetParent();
 236
 237     wxCHECK_RET( parent, _T("button without parent?") );
 238
 239     wxWindow *winOldDefault = parent->GetDefaultItem();
 240     parent->SetTmpDefaultItem(this);
 241     if ( winOldDefault != this )
 242     {
 243         UpdateDefaultStyle(this, winOldDefault);
 244     }
 245     //else: no styles to update
 246 }
 247
 248 void wxButton::UnsetTmpDefault()
 249 {
 250     wxWindow *parent = GetParent();
 251
 252     wxCHECK_RET( parent, _T("button without parent?") );
 253
 254     parent->SetTmpDefaultItem(NULL);
 255
 256     wxWindow *winOldDefault = parent->GetDefaultItem();
 257     if ( winOldDefault != this )
 258     {
 259         UpdateDefaultStyle(winOldDefault, this);
 260     }
 261     //else: we had been default before anyhow
 262 }
 263
 264 /* static */
 265 void
 266 wxButton::UpdateDefaultStyle(wxWindow *winDefault, wxWindow *winOldDefault)
 267 {
 268     // clear the BS_DEFPUSHBUTTON for the old default button
 269     wxButton *btnOldDefault = wxDynamicCast(winOldDefault, wxButton);
 270     if ( btnOldDefault && btnOldDefault != winDefault )
 271     {
 272         // remove the BS_DEFPUSHBUTTON style from the other button
 273         long style = ::GetWindowLong(GetHwndOf(btnOldDefault), GWL_STYLE);
 274
 275         // don't do it with the owner drawn buttons because it will reset
 276         // BS_OWNERDRAW style bit too (BS_OWNERDRAW & BS_DEFPUSHBUTTON != 0)!
 277         if ( (style & BS_OWNERDRAW) != BS_OWNERDRAW )
 278         {
 279             style &= ~BS_DEFPUSHBUTTON;
 280             ::SendMessage(GetHwndOf(btnOldDefault), BM_SETSTYLE, style, 1L);
 281         }
 282         else
 283         {
 284             // redraw the button - it will notice itself that it's not the
 285             // default one any longer
 286             btnOldDefault->Refresh();
 287         }
 288     }
 289
 290     // and set BS_DEFPUSHBUTTON for this button
 291     wxButton *btnDefault = wxDynamicCast(winDefault, wxButton);
 292     if ( btnDefault )
 293     {
 294         long style = ::GetWindowLong(GetHwndOf(btnDefault), GWL_STYLE);
 295         if ( (style & BS_OWNERDRAW) != BS_OWNERDRAW )
 296         {
 297             style |= BS_DEFPUSHBUTTON;
 298             ::SendMessage(GetHwndOf(btnDefault), BM_SETSTYLE, style, 1L);
 299         }
 300         else
 301         {
 302             btnDefault->Refresh();
 303         }
 304     }
 305 }
 306
 307 // ----------------------------------------------------------------------------
 308 // helpers
 309 // ----------------------------------------------------------------------------
 310
 311 bool wxButton::SendClickEvent()
 312 {
 313     wxCommandEvent event(wxEVT_COMMAND_BUTTON_CLICKED, GetId());
 314     event.SetEventObject(this);
 315
 316     return ProcessCommand(event);
 317 }
 318
 319 void wxButton::Command(wxCommandEvent & event)
 320 {
 321     ProcessCommand(event);
 322 }
 323
 324 // ----------------------------------------------------------------------------
 325 // event/message handlers
 326 // ----------------------------------------------------------------------------
 327
 328 bool wxButton::MSWCommand(WXUINT param, WXWORD WXUNUSED(id))
 329 {
 330     bool processed = FALSE;
 331     switch ( param )
 332     {
 333         case 1:                     // message came from an accelerator
 334         case BN_CLICKED:            // normal buttons send this
 335         case BN_DOUBLECLICKED:      // owner-drawn ones also send this
 336             processed = SendClickEvent();
 337             break;
 338     }
 339
 340     return processed;
 341 }
 342
 343 long wxButton::MSWWindowProc(WXUINT nMsg, WXWPARAM wParam, WXLPARAM lParam)
 344 {
 345     // when we receive focus, we want to temporary become the default button in
 346     // our parent panel so that pressing "Enter" would activate us -- and when
 347     // losing it we should restore the previous default button as well
 348     if ( nMsg == WM_SETFOCUS )
 349     {
 350         SetTmpDefault();
 351
 352         // let the default processing take place too
 353     }
 354     else if ( nMsg == WM_KILLFOCUS )
 355     {
 356         UnsetTmpDefault();
 357     }
 358     else if ( nMsg == WM_LBUTTONDBLCLK )
 359     {
 360         // emulate a click event to force an owner-drawn button to change its
 361         // appearance - without this, it won't do it
 362         (void)wxControl::MSWWindowProc(WM_LBUTTONDOWN, wParam, lParam);
 363
 364         // and continue with processing the message normally as well
 365     }
 366
 367     // let the base class do all real processing
 368     return wxControl::MSWWindowProc(nMsg, wParam, lParam);
 369 }
 370
 371 // ----------------------------------------------------------------------------
 372 // owner-drawn buttons support
 373 // ----------------------------------------------------------------------------
 374
 375 #ifdef __WIN32__
 376
 377 // drawing helpers
 378
 379 static void DrawButtonText(HDC hdc,
 380                            RECT *pRect,
 381                            const wxString& text,
 382                            COLORREF col)
 383 {
 384     COLORREF colOld = SetTextColor(hdc, col);
 385     int modeOld = SetBkMode(hdc, TRANSPARENT);
 386
 387     DrawText(hdc, text, text.length(), pRect,
 388              DT_CENTER | DT_VCENTER | DT_SINGLELINE);
 389
 390     SetBkMode(hdc, modeOld);
 391     SetTextColor(hdc, colOld);
 392 }
 393
 394 static void DrawRect(HDC hdc, const RECT& r)
 395 {
 396     MoveToEx(hdc, r.left, r.top, NULL);
 397     LineTo(hdc, r.right, r.top);
 398     LineTo(hdc, r.right, r.bottom);
 399     LineTo(hdc, r.left, r.bottom);
 400     LineTo(hdc, r.left, r.top);
 401 }
 402
 403 void wxButton::MakeOwnerDrawn()
 404 {
 405     long style = GetWindowLong(GetHwnd(), GWL_STYLE);
 406     if ( (style & BS_OWNERDRAW) != BS_OWNERDRAW )
 407     {
 408         // make it so
 409         style |= BS_OWNERDRAW;
 410         SetWindowLong(GetHwnd(), GWL_STYLE, style);
 411     }
 412 }
 413
 414 bool wxButton::SetBackgroundColour(const wxColour &colour)
 415 {
 416     if ( !wxControl::SetBackgroundColour(colour) )
 417     {
 418         // nothing to do
 419         return FALSE;
 420     }
 421
 422     MakeOwnerDrawn();
 423
 424     Refresh();
 425
 426     return TRUE;
 427 }
 428
 429 bool wxButton::SetForegroundColour(const wxColour &colour)
 430 {
 431     if ( !wxControl::SetForegroundColour(colour) )
 432     {
 433         // nothing to do
 434         return FALSE;
 435     }
 436
 437     MakeOwnerDrawn();
 438
 439     Refresh();
 440
 441     return TRUE;
 442 }
 443
 444 /*
 445    The button frame looks like this normally:
 446
 447    WWWWWWWWWWWWWWWWWWB
 448    WHHHHHHHHHHHHHHHHGB  W = white       (HILIGHT)
 449    WH               GB  H = light grey  (LIGHT)
 450    WH               GB  G = dark grey   (SHADOW)
 451    WH               GB  B = black       (DKSHADOW)
 452    WH               GB
 453    WGGGGGGGGGGGGGGGGGB
 454    BBBBBBBBBBBBBBBBBBB
 455
 456    When the button is selected, the button becomes like this (the total button
 457    size doesn't change):
 458
 459    BBBBBBBBBBBBBBBBBBB
 460    BWWWWWWWWWWWWWWWWBB
 461    BWHHHHHHHHHHHHHHGBB
 462    BWH             GBB
 463    BWH             GBB
 464    BWGGGGGGGGGGGGGGGBB
 465    BBBBBBBBBBBBBBBBBBB
 466    BBBBBBBBBBBBBBBBBBB
 467
 468    When the button is pushed (while selected) it is like:
 469
 470    BBBBBBBBBBBBBBBBBBB
 471    BGGGGGGGGGGGGGGGGGB
 472    BG               GB
 473    BG               GB
 474    BG               GB
 475    BG               GB
 476    BGGGGGGGGGGGGGGGGGB
 477    BBBBBBBBBBBBBBBBBBB
 478 */
 479
 480 static void DrawButtonFrame(HDC hdc, const RECT& rectBtn,
 481                             bool selected, bool pushed)
 482 {
 483     RECT r;
 484     CopyRect(&r, &rectBtn);
 485
 486     HPEN hpenBlack   = CreatePen(PS_SOLID, 1, GetSysColor(COLOR_3DDKSHADOW)),
 487          hpenGrey    = CreatePen(PS_SOLID, 1, GetSysColor(COLOR_3DSHADOW)),
 488          hpenLightGr = CreatePen(PS_SOLID, 1, GetSysColor(COLOR_3DLIGHT)),
 489          hpenWhite   = CreatePen(PS_SOLID, 1, GetSysColor(COLOR_3DHILIGHT));
 490
 491     HPEN hpenOld = (HPEN)SelectObject(hdc, hpenBlack);
 492
 493     r.right--;
 494     r.bottom--;
 495
 496     if ( pushed )
 497     {
 498         DrawRect(hdc, r);
 499
 500         (void)SelectObject(hdc, hpenGrey);
 501         InflateRect(&r, -1, -1);
 502
 503         DrawRect(hdc, r);
 504     }
 505     else // !pushed
 506     {
 507         if ( selected )
 508         {
 509             DrawRect(hdc, r);
 510
 511             InflateRect(&r, -1, -1);
 512         }
 513
 514         MoveToEx(hdc, r.left, r.bottom, NULL);
 515         LineTo(hdc, r.right, r.bottom);
 516         LineTo(hdc, r.right, r.top - 1);
 517
 518         (void)SelectObject(hdc, hpenWhite);
 519         MoveToEx(hdc, r.left, r.bottom - 1, NULL);
 520         LineTo(hdc, r.left, r.top);
 521         LineTo(hdc, r.right, r.top);
 522
 523         (void)SelectObject(hdc, hpenLightGr);
 524         MoveToEx(hdc, r.left + 1, r.bottom - 2, NULL);
 525         LineTo(hdc, r.left + 1, r.top + 1);
 526         LineTo(hdc, r.right - 1, r.top + 1);
 527
 528         (void)SelectObject(hdc, hpenGrey);
 529         MoveToEx(hdc, r.left + 1, r.bottom - 1, NULL);
 530         LineTo(hdc, r.right - 1, r.bottom - 1);
 531         LineTo(hdc, r.right - 1, r.top);
 532     }
 533
 534     (void)SelectObject(hdc, hpenOld);
 535     DeleteObject(hpenWhite);
 536     DeleteObject(hpenLightGr);
 537     DeleteObject(hpenGrey);
 538     DeleteObject(hpenBlack);
 539 }
 540
 541 bool wxButton::MSWOnDraw(WXDRAWITEMSTRUCT *wxdis)
 542 {
 543     LPDRAWITEMSTRUCT lpDIS = (LPDRAWITEMSTRUCT)wxdis;
 544
 545     RECT rectBtn;
 546     CopyRect(&rectBtn, &lpDIS->rcItem);
 547
 548     COLORREF colBg = wxColourToRGB(GetBackgroundColour()),
 549              colFg = wxColourToRGB(GetForegroundColour());
 550
 551     HDC hdc = lpDIS->hDC;
 552     UINT state = lpDIS->itemState;
 553
 554     // first, draw the background
 555     HBRUSH hbrushBackground = ::CreateSolidBrush(colBg);
 556
 557     FillRect(hdc, &rectBtn, hbrushBackground);
 558
 559     // draw the border for the current state
 560     bool selected = (state & ODS_SELECTED) != 0;
 561     if ( !selected )
 562     {
 563         wxPanel *panel = wxDynamicCast(GetParent(), wxPanel);
 564         if ( panel )
 565         {
 566             selected = panel->GetDefaultItem() == this;
 567         }
 568     }
 569     bool pushed = (SendMessage(GetHwnd(), BM_GETSTATE, 0, 0) & BST_PUSHED) != 0;
 570
 571     DrawButtonFrame(hdc, rectBtn, selected, pushed);
 572
 573     // draw the focus rect if needed
 574     if ( state & ODS_FOCUS )
 575     {
 576         RECT rectFocus;
 577         CopyRect(&rectFocus, &rectBtn);
 578
 579         // I don't know where does this constant come from, but this is how
 580         // Windows draws them
 581         InflateRect(&rectFocus, -4, -4);
 582
 583         DrawFocusRect(hdc, &rectFocus);
 584     }
 585
 586     if ( pushed )
 587     {
 588         // the label is shifted by 1 pixel to create "pushed" effect
 589         OffsetRect(&rectBtn, 1, 1);
 590     }
 591
 592     DrawButtonText(hdc, &rectBtn, GetLabel(),
 593                    state & ODS_DISABLED ? GetSysColor(COLOR_GRAYTEXT)
 594                                         : colFg);
 595
 596     ::DeleteObject(hbrushBackground);
 597
 598     return TRUE;
 599 }
 600
 601 #endif // __WIN32__
 602
 603 #endif // wxUSE_BUTTON
 604